The structure of [MoH(η-C5Me5)(CO)3] (1) has been determined by X-ray diffraction at 163(3) K [a = 6.969(2) Å, b = 12.651(2) Å, c = 7.954(2) Å, β = 103.36(2)°, monoclinic, P21/m (No. 11), Z = 2] and neutron diffraction at 163.0(5) K [a = 6.968(2) Å, b = 12.658(3) Å, c = 7.953(2) Å, β = 103.34(2)°]. Refinements in space group P21/m against both data sets improved the description of the structure obtained by refinements in P21 in this and an earlier study. The structure exhibits orientational disorder in the C5Me5 group, yet relatively accurate geometric parameters have been obtained, with esd's from the neutron diffraction study of 0.007 Å for Mo—H, 0.010 Å (average) for C—H, and 0.003 Å (average) for all other bond lengths. The molecule adopts a “four-legged piano stool” geometry with the hydride ligand approximately trans to one of the Cp* ring carbons [Mc—H(1) = 1.789(7) Å]. Comparison of the title complex with related d4 CpMo(CO)3L complexes (L = formally anionic, monodentate, η1 ligand) suggests that the conformation of these complexes is determined primarily by steric interactions between the ligand, L, and the Cp or Cp* ring, rather than by electronic effects of either Cp/Cp* or L.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry